nexVortex setup - registration issue

I recently setup a VOIP gateway with nexVortex to support testing the 3CX system. After I got my firewalls all set to map and pass the right ports, all seemed to work, except things just seemed "fragile".

Turns out that the registration process between 3CX and nV was having some difficulty, leading to multiple re-registrations that eventually hung things. Turning off registration seemed to fix the problem.

My question: Has anyone else experienced "registration" problems between 3CX and nV? Was there a way to configure registration so that it did not cause problems or instability?

Registration doesn't have an effect on you (other than the speed that connections are made). It's only important when the provider requires it, which I thought nV did. I am surprised it is working without it.

Our Internet-facing firewall is a Netopia R9100, running NAT. The LAN side of the Netopia is on our perimeter LAN. Between the perimeter LAN and our inner LAN (where the 3CX server is located) is a Netgear FVS124G in classical routing (no NAT) mode.

Ports 5060, 5061, 3478, 9000-9499 and 10000-20000 are mapped through the NAT router to point to the 3CX box. Traffic is allowed on these ports through the Netgear non-NAT router.